Complete XP slowdown..... Help please!!!!

Alright i just bought a 200 gig Western Digital drive and it came with an ultra ata controller so i slaved my 40 gig and installed windows xp fresh on my 200 gig... Since installation I am getting the slowest XP performance i have gotten in the last 2 years. System sounds pop and skip and the mouse pointer lags. My buddy said booting off an ultra ata controller could cause performance issues because the pci bus is much slower then the ide bus but this is outrageous! I just installed windows on it last night and it hangs at the spash screen for a good 2 minutes and the screen goes black for another minute before showing the login screen... Help me please!!!!